first = float(input("请输入第一个数: "))
second = float(input("请输入第二个数: "))
operator = input("请选择运算符: + - * /:")
if operator == '+':
    print(first + second)
elif operator == '-':
    print(first - second)
elif operator == '*':
    print(first * second)
elif operator == '/':
     if second == 0:
         print("除数不能为0")
     else:
         print(first / second)
guess_num = input("请设定猜数的数值: \n")
for frequency in range(1,6):
    number = input("请输入第"+str(frequency)+"次猜测的数:")
    if number.isdigit() is False:
        print('请输入一个正确的数字')
    elif int(number) < 0 or int(number)>100:
        print("请输入1-100范围的数字")
    elif int(guess_num) == int(number):
        print("恭喜你用了%d次猜对了" % frequency)
        break
    elif int(guess_num) > int(number):
        print("很遗憾，你猜小了")
    else:
        print("很遗憾，你猜大了")
    if frequency == 5:
        print("很遗憾，%d次机会已用尽，游戏结束，答案为%d" %(frequency,int(guess_num)))
    
for i in range(1, 101):
    if "7" in str(i) or int(i) % 7 == 0:
        print('*', end="、")
    elif "7" not in str(i)and int(i) % 7 != 0:
        print(i, end='、')
        
size = int(input("请输入棋盘的大小："))
for i in range(size):
    for j in range(size):
        if i == 0 and j ==0:
            print("┏",end='')
        elif i == 0 and j == size - 1:
            print("┓",end='')
        elif i == size - 1 and j == 0:
            print("┗",end='')
        elif i == size - 1 and j == size - 1:
            print("┛",end='')
        elif j == 0:
            print("┠",end='')
        elif i == size - 1:
            print("┷",end='')
        elif j == size - 1:
            print("┨",end='')
        elif i == 0:
            print("┯",end='')
        else:
            print("┼",end='')
        print('')
